DNA testing is not mandatory.
As DNA testing is not mandatory, you do not have to undertake DNA testing when its use by Immigration is suggested.
DNA testing is just another form of evidence to be used when Immigration need to validate certain aspects of a relationship. For example, to confirm that the stated father is the birth father of the child. Not every application will suggest a DNA test.
If you decide to undertake DNA testing, the Department provides information on how to arrange a test that will meet the Department’s requirements. Any test obtained outside these requirements may not be accepted.
If you decide not to undertake DNA testing, a decision on your visa or citizenship by descent application will be made using only the information available to the Department at that time.
You need to think about the above statements.
Immigration have probably suggested a DNA test as they are not currently prepared to grant citizenship based only on the information so far available.
A confirmed DNA test would presumably confirm what they need to know.
A refusal to do a DNA test might also confirm something to them.
Form 1259i provides the information about DNA testing for visa and citizenship applicants. It explains the DNA testing process.
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